Cheap flights from Seattle to Ontario (SEA - ONT)

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The best prices from Seattle/Tacoma Intl to Ontario are usually found in September or October, booked 59 days in advance, depart on a Wednesday or Thursday and return on a Friday

How to find the cheapest flight from
Seattle (SEA) to Ontario (ONT)

All the information you need to plan the best SEA to ONT flight in 2022: compare Seattle to Ontario flight prices with the expected peak season, weather and rainfall in Ontario.
SEA - ONT
Price
$157 - $367
ONT
Temperature
53.6 - 78.8 °F
ONT
Rainfall
0.1 - 3.4 inches

Popular in

June

High demand for flights, 33% potential price rise

Cheapest in

September

Best time to find cheap flights, 36% potential price drop

Round-trip from

$157

From Seattle/Tacoma Intl to Ontario

One-way from

$89

One-way flight from Seattle/Tacoma Intl to Ontario

Flight route prices based on searches on Cheapflights within the last 3 days, monthly prices based on aggregated historical data.
When is the cheapest time to fly from Seattle to Ontario (SEA - ONT)?

A simple way to save on the total cost of your ticket is to fly from Seattle to Ontario in the afternoon. If you’re flexible enough to do this you can expect to save up to 38% on your trip compared to booking a flight at noon.

What is the cheapest month to fly from Seattle to Ontario?

Flights from Seattle to Ontario lean towards being more expensive in June. Prices are generally better when you fly from Seattle to Ontario in October, with the cheapest ticket starting at $115.

How far in advance should I book a flight from Seattle to Ontario?

Users have found that booking a flight from Seattle to Ontario at least 61 days early can save you up to 85% on average compared to booking a flight this week. If booking 61 days before your flight isn’t an option for you, users have found flights from Seattle to Ontario for as little as $278 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $363 for flights departing within the next 3 days.

What is the cheapest day to fly round-trip from Seattle to Ontario?

Flying to your destination on a Sunday can be more expensive, but this shouldn’t discourage you from finding affordable options to get to Ontario. Check prices with Cheapflights to find a great deal for your trip.

Cheap flights from Seattle to Ontario in August, September 2022

The best prices found for SEA to ONT flights for August, September
13 Sep - 14 Sep
$147pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Multiple Airlines
 
1 STOP
SEA
Seattle/Tacoma Intl
28 Sep - 4 Oct
$153pp
SEA
Seattle/Tacoma Intl
Frontier
 
1 STOP
ONT
Ontario
ONT
Ontario
Frontier
 
1 STOP
SEA
Seattle/Tacoma Intl
24 Sep - 11 Oct
$156pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl

Seattle/Tacoma Intl to Ontario 2022 flight deals

Cheap flights to Ontario from Seattle found for this year
13 Sep - 14 Sep
$147pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Multiple Airlines
 
1 STOP
SEA
Seattle/Tacoma Intl
28 Sep - 4 Oct
$153pp
SEA
Seattle/Tacoma Intl
Frontier
 
1 STOP
ONT
Ontario
ONT
Ontario
Frontier
 
1 STOP
SEA
Seattle/Tacoma Intl
24 Sep - 11 Oct
$156pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl

Cheap Frontier flights from Seattle to Ontario

28 Sep - 4 Oct
$153pp
SEA
Seattle/Tacoma Intl
Frontier
 
1 STOP
ONT
Ontario
ONT
Ontario
Frontier
 
1 STOP
SEA
Seattle/Tacoma Intl
20 Sep - 23 Sep
$164pp
SEA
Seattle/Tacoma Intl
Frontier
 
1 STOP
ONT
Ontario
ONT
Ontario
Frontier
 
1 STOP
SEA
Seattle/Tacoma Intl
29 Sep - 3 Oct
$167pp
SEA
Seattle/Tacoma Intl
Frontier
 
1 STOP
ONT
Ontario
ONT
Ontario
Frontier
 
1 STOP
SEA
Seattle/Tacoma Intl

One of the most popular airlines traveling from Seattle to Ontario is Frontier. Flights from Frontier traveling this route typically cost $217.62 RT. This price is typically 71% cheaper than other airlines that offer Seattle to Ontario flights. When booking this route, the cheapest RT price found was $91. Seattle/Tacoma Intl Airport is the most common Seattle airport to take off from when flying to Ontario. Ontario Airport is the most popular arrival airport in Ontario. When flying from Seattle to Ontario, Frontier flights are 30% more popular than any other airline flying that same route.

Cheap United Airlines flights from Seattle to Ontario

18 Oct - 26 Oct
$196pp
SEA
Seattle/Tacoma Intl
United Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
United Airlines
 
1 STOP
SEA
Seattle/Tacoma Intl

Alaska Airlines is one of the most popular airlines used for those traveling from Seattle to Ontario. Flights on this route from Alaska Airlines typically cost $286.81 RT, a price that is 62% cheaper than the average Seattle to Ontario flight. The cheapest flight found was $98 RT. Seattle/Tacoma Intl Airport is the most common Seattle airport to take off from when flying to Ontario. Ontario Airport is the most popular arrival airport in Ontario. When flying from Seattle to Ontario, Alaska Airlines flights are 30% more popular than any other airline flying that same route.

Non-stop flights to Ontario from Seattle

Save time with Seattle to Ontario direct flight deals
24 Sep - 11 Oct
$172pp
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
14 Sep - 14 Sep
$173pp
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
21 Sep - 24 Sep
$175pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
Non-Stop
ONT
Ontario
ONT
Ontario
Delta
Non-Stop
SEA
Seattle/Tacoma Intl

Last minute flights from Seattle to Ontario

Late deals on round-trip flights to Ontario from Seattle, departing today and this week
11 Aug - 22 Aug
$294pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
11 Aug - 22 Aug
$298pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Multiple Airlines
 
1 STOP
SEA
Seattle/Tacoma Intl
9 Aug - 16 Aug
$337pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario
ONT
Ontario
Multiple Airlines
 
1 STOP
SEA
Seattle/Tacoma Intl

One-way flights to Ontario from Seattle

The cheapest one-way flights from Seattle to Ontario
4:20 am - 7:05 am
Delta
Nonstop
2h 45m
SEA - ONT
Delta
$89
Delta
8:38 am - 12:24 pm
Frontier
1 Stop
27h 46m
SEA - ONT
Frontier
$110
Kiwi.com
8:00 am - 3:09 am
Multiple Airlines
1 Stop
19h 09m
SEA - ONT
Multiple Airlines
$117
Kiwi.com

Related info for your journey

Useful info, stats and facts about <span class="emphasized">Seattle</span> to <span class="emphasized">Ontario</span> flights.

Flight FAQs

From Seattle to Ontario

What airports do I use to fly from Seattle to Ontario?

Booking a flight from Seattle/Tacoma Intl (SEA) to Ontario (ONT) is your only option if you wish to fly from Seattle to Ontario. On a typical day, there are 11 flights from Seattle/Tacoma Intl to Ontario, all of which are around 2h 30m for a nonstop flight. You can also purchase a plane ticket from 9 airlines when you book a flight from Seattle/Tacoma Intl to Ontario.

Which airlines flying from Seattle/Tacoma Intl to Ontario have flexible cancellations due to COVID-19?

Due to the rapidly changing circumstances due to COVID-19, airlines like Alaska Airlines, Delta, and Juneyao Airlines flying from Seattle/Tacoma Intl to Ontario have implemented new flexible cancellation policies.

Can I find flights from Seattle to Ontario for under $200 on Cheapflights?

Yes, there are multiple flights from Seattle to Ontario for under $200. The cheapest flight booked recently is on Multiple Airlines for just $147, but on average you can expect to pay $166.

Are there nonstop flights from Seattle to Ontario for under $200 on Cheapflights?

Cheapflights has at least 20 direct flights from Seattle to Ontario under $200. A good price for a nonstop flight from Seattle to Ontario is less than $194.

Are there last-minute flights available from Seattle to Ontario for under $300?

There are currently 20+ open flights from Seattle to Ontario within the next 7 days for less than $300.

What days are nonstop flights available from Seattle to Ontario?

You can find nonstop flights on the following days: Thursday.

How popular is this Seattle to Ontario flight route?

This flight path from Seattle/Tacoma Intl to Ontario was viewed by 54 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

How many flights depart from Seattle to Ontario on average per day?

Travelers can expect 2 flights from Seattle to Ontario on average per day.
Evening (6pm - Midnight) - 100% of flight departures

How long is the flight from Seattle to Ontario?

A quick flight from Seattle to Ontario can take about 2h 41m. Frontier provides one of the quickest options available for as low as $153. The distance from Seattle to Ontario is about 962 mi. Both multi-stop and nonstop flights can be found to your destination and back.

What are the cheapest airlines flying from Seattle to Ontario round-trip?

Our cheapest airline available from Seattle to Ontario is Frontier. Our recent data shows that you can find tickets from as low as $153 on this airline. An additional option worth looking into is Alaska Airlines, starting at $176. Frontier is priced at 37% lower than the current average price of a flight leaving 3 months from now.

What are the cheapest airlines to fly from Seattle to Ontario one-way?

For one-way options, check prices for Frontier. According to our data, you can fly for as low as $76. Users have also found prices from $89 and $92 on Delta and Alaska Airlines, respectively.

What are the cheapest flights from Seattle to Ontario?

Looking at all options, your cheapest flight can be booked for $89. While the most popular route (Seattle/Tacoma Intl - Ontario) can be booked for $147 on average our data indicates $455 when flying from Seattle to Ontario.

What are the most reliable airlines from Seattle to Ontario?

Before booking your flight to Ontario from Seattle, check out the most reliable airlines to get you to your destination on time: KLM (97%), Virgin Atlantic (94%), SkyWest Airlines( 92%).

What are the most popular airlines that fly from Seattle to Ontario?

American Airlines, Alaska Airlines and Delta are the most popular airlines when flying from Seattle to Ontario.

COVID Restrictions

View COVID Travel Restrictions for Ontario, CA

Do I need a COVID test to fly to Ontario from Seattle?

Information is based on travel restrictions for travel to Ontario within the United States

Most visitors from Seattle/Tacoma Intl need to provide a negative COVID-19 test result and/or quarantine to enter Ontario.

COVID-19 testing requirements
Visitors from Seattle/Tacoma Intl are not required to present a negative COVID-19 PCR test or antigen result upon entering Ontario.

Quarantine requirements
Visitors from Seattle/Tacoma Intl are not required to quarantine after entering Ontario.

Do I need a test to fly back to Seattle from Ontario?

Returning to Seattle/Tacoma Intl from Ontario

COVID-19 testing requirements
Visitors from Ontario are not required to present a negative COVID-19 PCR test or antigen result upon entering Seattle/Tacoma Intl.

Quarantine requirements
Visitors from Ontario are not required to quarantine after entering Seattle/Tacoma Intl.

Hide COVID Travel Restrictions for Ontario, CA

Alternative routes for Seattle to Ontario

See prices for flight routes from nearby airports that may be better suited for you.

Top 4 airlines flying from Seattle/Tacoma Intl to Ontario

The chart below displays the airlines Cheapflights users traveling from Seattle to Ontario choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
Airline Cheapest Average Flexibility On-time COVID-19 safety
Juneyao Airlines
$14 $22 No cancel fee 66%

We couldn't confirm the COVID-19 safety measures taken by Juneyao Airlines. Please check directly on their website for additional information.

United Airlines
$71 $304 No cancel fee 69%
Alaska Airlines
$91 $218 No cancel fee 75%
Delta
$98 $287 No cancel fee N/A

Hourly flight availability from Seattle to Ontario

See what time of day planes typically take off from Seattle towards Ontario.
Afternoon Noon to 6 PM 43% of SEA to ONT departures
Evening 6 PM to midnight 39% of SEA to ONT departures
Early morning Midnight to 6 AM 11% of SEA to ONT departures
Morning 6 AM to noon 7% of SEA to ONT departures
Midnight
6 AM
Noon
6 PM
Weekly flight availability
from Seattle to Ontario
See how many times per day planes take to the skies headed from Seattle to Ontario.
Sunday
12 daily flights
Monday
12 daily flights
Tuesday
12 daily flights
Wednesday
12 daily flights
Thursday
12 daily flights
Friday
12 daily flights
Saturday
10 daily flights